Ethanol From Carbon Dioxide Is Still A Losing Proposition

If I told you that I had created a process to extract pure gold from seawater, you might deem it an amazing accomplishment. If I issued a press release stating these facts, it very well could go viral.

In fact, the oceans do contain an estimated 20 million tons of dissolved gold, worth close to a quadrillion dollars at the current spot market price. But you may have noticed that I have omitted a very important fact.

I haven’t mentioned how much it costs to produce a troy ounce of gold using the process I have designed. That seems like an important detail, so I explain that the production cost is only $50,000 or so per ounce (which today is worth about $1,265), but I am sure that with enough investment dollars — and maybe a few government subsidies — I can get that cost down to something more reasonable. (This is how we subsidize some advanced biofuels where production costs are an order of magnitude above what could be considered economical).

Readers immediately understand the problem. You don’t spend more to produce something than you can sell it for. But change the equation to energy instead of money and people suddenly forget that lesson. Or they fail to recognize that is what is taking place.

That brings me to the point of today’s article, one I’m forced to reiterate often: in the world of energy as in most others, there is no free lunch.

Earlier this month a research paper was published by the Department of Energy’s Oak Ridge National Laboratory (ORNL) called “High-Selectivity Electrochemical Conversion of CO2 to Ethanol using a Copper Nanoparticle/N-Doped Graphene Electrode.” The paper reports on some truly interesting science, and the researchers were measured and cautious in their conclusions.

But something got lost in translation as media outlets sought to portray this as a “holy grail,” “game changer,” “major breakthrough” or “solution to climate change.” The benefits, one story said, were unimaginable. Part of the problem, in my opinion, is that the press release from the Department of Energy was titled Scientists Accidentally Turned CO2 Into Ethanol.

The word “accidental” plays into the misconception people have of how science is done. Many take the romantic view that game-changing, eureka discoveries are merely awaiting the next lucky accident, so when they read this headline the translation becomes something like “New Discovery Solves Climate Change.”

That’s because the public loves its energy miracles. People love the idea of a car that can run on water or the car that gets 400 miles per gallon (which of course GM and Ford suppressed) or the magic pill you can pop in your tank that greatly enhances fuel efficiency. So it isn’t surprising that this kind of story goes viral (in notable contrast to the articles debunking these viral stories.)

In order to understand what’s really going on, let’s consider a fundamental principle of thermodynamics.

If you burn something containing a combination of carbon, hydrogen, and oxygen — e.g., gasoline, ethanol, wood, natural gas — that combustion reaction is going to produce heat, carbon dioxide and water. These are the combustion products.

It is possible to reverse the combustion reaction and convert that water and carbon dioxide back into fuel. But you have to add heat. A lot of heat. How much? More than you can get from burning the fuel in the first place. No new catalyst, and no discovery, accidental or otherwise, can get around that fundamental issue without overturning scientific laws observed and confirmed over 150 years.

Given that, what can we say immediately about this process? Going back to the fundamentals of thermodynamics, we can say, without a doubt, that the process consumes more energy than it produces. In other words, to produce 1 British thermal unit (BTU) of ethanol will require the initial consumption of more than 1 BTU of energy (and generate CO2 emissions.) The resulting 1 BTU of ethanol would ultimately be consumed. The net effect once the ethanol is consumed is more than 2 BTUs’ worth of emissions per BTU of ethanol produced. Or, to be blunt, unless the process can be run on excess renewable or nuclear power (more on that below), converting carbon dioxide into ethanol would actually worsen net carbon dioxide emissions.

Now the researchers involved certainly know this. They actually acknowledged in the paper that the process is unlikely to be economically viable. To my knowledge they haven’t intentionally misled anyone.

But the public has been misled in the retelling of the story. I have heard this research presented as “an efficient way of removing carbon dioxide from the atmosphere.” No, that’s not at all what the researchers claimed. They claimed a Faradaic efficiency in the process of 63%. In other words, 63% of the electricity used in process was utilized in the reaction. They further said that 84% of what was produced was ethanol. That’s the “high-selectivity” part of the title.

But that says nothing at all about the energy consumption required to remove carbon dioxide from the atmosphere so it can participate in this reaction. That is an enormous energy cost because carbon dioxide exists at only 400 parts per million in the atmosphere. Or in the case of passive removal (which is what plants do by means of photosynthesis), the process is very slow.

The high Faradaic efficiency and selectivity also provide little information about the overall energy requirements to turn purified carbon dioxide into purified ethanol, but we already know that it’s more than the energy contained in the ethanol. And it could be a lot more, and that could result in a lot more carbon dioxide emissions.

There is a way that a process like this that is an energy sink could be viable, and that would be if you had cheap, surplus energy that might otherwise be wasted. For example, if a wind farm or nuclear plant produced far more electricity than the grid could handle, you could envision dumping the excess power into such a process. That could in theory reduce carbon dioxide emissions, but there are a lot of caveats that would warrant a longer discussion. Such an intermittent process brings up its own set of issues, and then there’s the question of whether that would really be the best use of the surplus energy.

The bottom line here is if someone presents a scheme for turning air, water, or carbon dioxide into fuel, it is necessarily consumes more energy than it produces. It is an energy sink.

Now, I need to get back to processing ocean water, just as soon as I finish writing this grant proposal for the process.

Storage is another category of holy grail. There are losses from the act of storing it and then more losses from the act of retrieving it in addition to the cost of the storage machinery. Storage has always been viewed as the answer to intermittency, but the idea is starting to lose steam. Read:http://euanmearns.com/el-hierro-completes-a-year-of-full-operation/

It may not be a good evaluation as the hydro storage is currently limited to 20% of planned and the wind turbines throttled to 70%. Both for what ever reason, the author has no info upon. Bring those two variables up to design intent would have a major impact on results.

So, given the solar hydrological cycle does away with pumping loss, hydro has 2x the benefit to power production and can act as a energy storage. Shouldn’t the thousands of dams we already have in place first be converted to power generation? Analysis project a doubling of this, our most valuable power is possible at little environmental costs other than change. Where I live they build dams just to affect change and enjoy flowage reserve for recreation economy.

The author has extensive information on it, you just have yet to read it.

Now the system could not scale up because of the size limitations of the geological features on the island. That said the project proposers said that 63% (and sometimes 100%) of electricity would come from this system after the design had been proposed. They got it well wrong.

Ironically you could make the very same arguments against almost any form of energy. For example it costs money and energy to pump oil out of the ground, more to transport it and store, first in leased storage, then in ships and sometimes back and forth between the two , depending on contango, and finally to over the road trucks and into our SUVs which burn said fuel at 20 percent thermal efficiency. We should probably also factor in the costs and energy of massive fleets of warships to protect access to cheap oil and the ever increasing costs of finding and getting it out of the ground in the first place. At some point the EROI will make oil impractical as a motor fuel.

Large scale pumped hydro has been used effectively for decades, so that part of the process is not flawed and runs counter to your assertion that any process that costs energy is unworkable.

There are reasons we only get 2% of our electricity from pumped hydro. In a few places it can be profitable, but obviously, not always. I wouldn’t call it flawed. I’d call it hard to make a profit.

I never said that any process that costs energy is unworkable. The losses from storage are in addition to all of the other losses from making the energy in the first place. They represent additional losses which makes it that much harder to be profitable, as the low amount of pumped hydro attests.

Apologies for re-interpreting what you meant by storage “losing steam”. Obviously pumped hydro is not practical in many situations, thus my interest in alternative forms of storage. Storage has been used effectively to leverage excess capacity on nights and weekends and makes even more sense for intermittent renewables. You make a fair point about our current under-utilization, fortunately attitudes seem to be changing and storage is on the rise globally , “Pumped storage hydro is growing fastest in China, with 10 or 15 projects under construction.” – http://e360.yale.edu/feature/for_storing_electricity_utilities_are_turning_to_pumped_hydro/2934/

The scientific news story I read emphasized the discovery as a break through in that copper could replace expensive precious metals that had been required for such a process. The nano technology had spikes or dendrites like structures of copper that acted similar to the platinum alloy . Also, they discovered ethanol in the mix, something new. Possible exploitation of this discovery include a new class of chemical battery or possible catalytic process to convert the pure CO2 waste stream of ethanol fermentation process to additional ethanol production. Note: both processes require additional power, but serve as more valuable process of energy storage or pollution control.

As you know, often times solar energy of wind or sunshine suffers from variable and unpredictable power production. This is very bad for electric power as compared to variable production of natural gas or fuel that is easy to store. This discovery may provide a path for solar energy to store energy production per liquid fuel. Same for pure CO2 waste streams that could push waste through a catalytic converter with electric power to eliminate the waste at a energy cost.

Good call on this story Robert. I saw the first clips of this and immediately looked up the actual paper. In the paper itself the authors state that it is not economically viable to produce ethanol this way. Like you said everyone else ran with it. Also, they didn’t just accidentally make fuel, their hypothesis was that they could use this process to make methanol, the accident was that a side reaction made more ethanol instead.

As for whether this is an efficient use of surplus energy, I don’t know. But I do know there are a lot of windmills in rural Minnesota that sit idle on windy days anytime its not the middle of summer. The same goes for South Dakota and Iowa. These places also have pure CO2 that lacks market access. Unless someone is going to bring batteries out here so we can continue to run the windmills, we might as well use the power for something like this. I’m all for whatever we want to pump this surplus energy into if there is a better solution, but it doesn’t seem the grid can handle it so we need to find something useful for them to do. Maybe this is part of that solution.

It is surprising to me, to read basic science research and to gain an understanding on how much we do not understand. The report on JILA team using laser spectroscopy operating through glass dome to ID chemical reactions. Basic reactions of ICE engine combustion. They vary input constituents to map out generation of chemical power and pollution. They plan to study CO2 and water reactions to understand better the process on why oceans acidify. You see this is basic stuff and a foundation to build better solutions. Up until know scientist only had theories (no actual observation of real time chemistry) of the combustion and interplay of water, nitrogen, carbon fuel, extreme pressure and heat. So, how can are environmental scientist plot out our future time frame of demise per exact GW science? They can’t it’s just an exercise in speculation that is hyped up per our political journalist, that neglect to inform the public of the inaccuracy of the science.

Science hadn’t known that CO2 could directly be converted to ethanol and done with low cost alloy. By the discovery and investigation, this will lead us to better understanding of the science and as a result will move the bar upwards to better more cost effective solutions.

I read a updated study (White Paper) on auto technology as the old five year study was already inaccurate as technology advanced. We take these snapshots of static conditions and attempt to extrapolate the future. GW and renewable power enthusiast both continually make inaccurate projections and do so upon historical trends, (the most out of date data possible). Activist journalist will again hype such sketchy info to public for fear mongering and do so I believe for their trade union political gain and personal promotion. So, if we could possible divert or subvert this entertainment science to educate and inform the public of the true merits of the science, we would indeed have a powerful nation of truly educated thinkers. Just saying.